With Boeing facing multiple government investigations, the company needs to make “a serious transformation” around its safety and manufacturing quality, Transportation Secretary Pete Buttigieg said Monday.

The comments came one day after Buttigieg said the aircraft builder is under “enormous” scrutiny by his department since a panel blew off a Boeing 737 Max jetliner in midlfight.

Over the weekend, The Wall Street Journal reported that the Department of Justice launched a criminal investigation into the Jan. 5 blowout on an Alaska Airlines jet. That followed the company’s admission that it couldn’t find records that the National Transportation Safety Board sought for work done on the panel at a Boeing factory.

The Federal Aviation Administration, part of Buttigieg’s department, is also investigating Boeing.

“Obviously we respect the independence of DOJ (the Department of Justice) and NTSB (the National Transportation Safety Board) doing their own work,” Buttigieg told reporters Monday, “but we are not neutral on the question of whether Boeing should fully cooperate with any entity — NTSB, us, or DOJ. They should, and we expect them to.”

Buttigieg said Boeing must “go through a serious transformation here in terms of their responsiveness, their culture and their quality issues.”

Boeing gave a one-sentence response.

“We will continue to cooperate fully and transparently with all government investigations and audits, as we take comprehensive action to improve safety and quality at Boeing,” the company said.

Alaska Airlines said it is cooperating with the Justice Department investigation.

“In an event like this, it’s normal for the DOJ to be conducting an investigation,” the Seattle-based airline said in a statement. “We are fully cooperating and do not believe we are a target of the investigation.”

Last week, Boeing, which is based in Arlington, Virginia, came under withering criticism by NTSB Chair Jennifer Homendy over the missing work records on the Alaska jet. She told a Senate committee that Boeing had repeatedly rebuffed her agency’s attempts to get information ever since the blowout. Boeing disputed some of Homendy’s claims; NTSB stood by her testimony.

The FAA has barred Boeing from boosting production of Max jets and gave the company 90 days to come up with a plan to fix quality-control issues.